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From New Latin ballistica + -s, use as noun of feminine of ballisticus (“ballistic”). Compare later ballistic and French balistique. By surface analysis, ballista + -ics or ballistic + -s.
Etymology from Wiktionary, CC BY-SA 4.0.
ballistics
Today it means: The science of objects that predominantly fly under the effects of gravity, momentum and atmospheric drag, and dealing with details of their behaviour at the origin and destination of their flight, as of bullets or missiles or rockets. Full definition →